Throughout the United States innumerable earthen trenches are excavated annually. Such trenches are employed in the construction of engineering structures ranging from building foundations to sewer lines. The laborers assembling such structures are often required to work within these trenches. Often they are fatally injured while doing so.
While trenches may be excavated to a depth greater than a man's height, they seldom penetrate the relatively unconsolidated soils or sediments that overlay solid bedrock below. This unconsolidated matter is usually a mixture of decaying vegetative material and fine-grained wind or water borne minerals. When exposed by an excavation such as a trench, these materials have proven to be extremely unstable and prone to cave-in under the slightest load. Thus, the possibility of an excavation's collapse is always substantial. Indeed, it has been estimated that two hundred fatalities caused by trench cave-ins occur within the United States each year.
Construction companies are notoriously lax in obeying regulations promulgated by government agencies. Regulations of the Occupational Health and Safety Administration (OSHA), for instance, mandate that trenches or excavations of a depth greater than an established minimum must be sloped or shored. As the sloping of excavations is a time consuming process requiring the movement of earthen material beyond that absolutely necessary for construction purposes, it is avoided when possible to reduce expenditures. Additionally, the trench boxes currently available for shoring trenches are time consuming to erect at construction sites due to their large size, weight, and complexity. Beyond this, trench box cross braces restrict and impede free movement within the trench as well as the rate at which work can be performed. Since construction companies usually establish goals of performing assignments as rapidly as possible, neither trench shoring nor sloping operations are performed without great hesitation and reluctance. As long as this remains the case, the risk to human life at construction sites will remain unnecessarily high.
The need has arisen for an apparatus which will prevent the cave-in of an earthen trench and may be erected rapidly at the construction site.